<!DOCTYPE html>
<html>
  <head>
    <style>
      input ~ label {color: red}
      input:not(:default):not(:checked):not([checked]) ~ label {color:red}
      input[checked]:checked:default ~ label {color: green}
    </style>
  </head>
  <body onload='document.getElementById("one").setAttribute("checked", "checked");'>
    <form>
      <input type="checkbox" name="group1" id="one" value="1"/>
      <label for="one">Should be no red</label><br>
      <input type="checkbox" name="group1" id="two" value="2"/>
      <label for="two">Should be no red</label>
    </form>
  </body>
</html>
